The Russian National Orchestra is not very old, established only in 1990, in the last days of the Soviet Union. But it has long seemed part of the furniture. The RNO came to Avery Fisher Hall for two concerts over the weekend. It was conducted by Vladimir Jurowski, the young, dynamic maestro with the fabulous long hair — “conductor’s hair.”

On Saturday night, the menu was Schubert and Brahms — beginning with the Symphony No. 8 in B minor by Schubert. This is the symphony in two movements, the “Unfinished,” as you know.

From Mr. Jurowski and the RNO, it started ominous and dark — very dark. The traditional Russian darkness served the opening measures very well. When the music really got going, Mr. Jurowski chose a very, very fast tempo. Given this tempo, it seemed that some of the mystery would be taken out of the symphony. The first movement is marked “Allegro moderato”; “moderato” seemed nowhere to be found.

But a funny thing happened, as the symphony continued. The ear adjusted; Mr. Jurowski’s tempo seemed almost normal.

In the main, he exhibited good taste, judging the pauses decently, for example. Critical parts of the first movement were very, very moving. And we were reminded what a great work this is.

Occasionally, the orchestra sounded tight and dry. But, overall, it satisfied. Some of the onsets were shaky, and some of the chords were not together. But the unison playing of the strings tended to be extraordinarily smooth. And the brass were fairly poised and accurate.

As for the second movement, Mr. Jurowski was again on the fast side, but sensible. His dynamics were acute — sometimes startling — but not un-Schubertian. He kept things interesting, in a movement that careless hands can make monotonous. In their solos, the woodwinds were adequate. But the orchestra was best when playing as one, and in full cry.

The conductor launched right into the third movement, allowing hardly any break. What, the third movement? Yes: Mr. Jurowski was conducting a “completion” by Anton Safronov, a Russian composer in his 30s. Schubert left a piano outline of a third movement; so Mr. Safronov imagined how that would have come out. And he went ahead and composed a fourth movement — though borrowing from music of Schubert that we actually have. (A piece for piano four hands; an unfinished piano sonata.)

That third movement was bumptious, exuberant, and plausibly Schubertian. And the RNO’s horns did admirable work. The last movement proved interesting and earnest — intelligently crafted, generally in line with Schubert’s spirit. We heard neat little allusions to the opening movement. Mr. Safronov has performed more an act of devotion than an act of ego or hubris.

But I, personally, must question such exercises. To me, the two additional movements seem superfluous. They also make the symphony unnaturally long, in my judgment. It felt like a week in B minor. Schumann famously said that Schubert’s Symphony No. 9 had “heavenly length.” I’m not sure that the length of the Schubert/Safronov Eighth is so heavenly.

Herewith a rule: Unless you’re a genius, leave such uncompleted works as Schubert’s Eighth and Mahler’s Tenth alone. And if you do happen to be a genius — spend your time on your own stuff!

After intermission, we had Brahms’s Piano Concerto No. 1 in D minor, in which the soloist was Stephen Hough. He has long been underrated, or at least underfamous: He has no PR machine behind him (apparently). And he seems the type who would not want one. He is a pure, honest musician, and one of the best pianists in the world.

He is the kind of pianist — very rare — who contains all pianists. He is a thunderous and dazzling virtuoso; and he is a poet, a miniaturist. He is both a Liszt player and a Mozart player — utterly appropriate in both. He has Horowitz in him, and also Myra Hess. (Actually, those two pianists contained all elements too.) Mr. Hough, in brief, is a complete pianist. He does not have much company. Among living pianists, there is Yefim Bronfman, and a handful of others.

In the Brahms D-minor, Mr. Hough called on his completeness: He was titanic and angelic, as the music required. In almost every note and phrase he played, there was judgment. The second movement had all the spirituality imbedded in it. And Mr. Jurowski and the Russian National Orchestra made excellent, committed partners in Brahms. They used head and heart in the right doses.

You could issue some complaints, of course — sometimes Mr. Hough sounded a little brittle. (And then there were the bright red shoes.) But, in perspective, any complaints would be trivial. This was a first-class performance of a great concerto. The audience got its money’s worth, and then some.